how do i get the bond dissociation energy to break 7 C-H bond(s) in 1 mole of propane (CH₃CH₂CH₃) molecules is

Explanation:

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In this case, since the bond energy per C-H bond is 411 kJ/mol and we of course avoid the C-C bond since we are asked to compute the energy to break 7 C-H bonds, the 411 kJ/mol are multiplied by 7 as shown below:

Thus, we obtain the required bond dissociation energy. Note that propane CH₃-CH₂-CH₃ has seven C-H bonds; 3 from the first CH₃, two from the CH₂ and 3 from the last CH₃.

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